There are many situations in which it is necessary to attach an unflanged pipe to a flanged member. Such a situation exists when a pipe is to be attached to a valve having an attaching flange. In the past, when the pipe has been made of steel or cast iron, it has been common practice to use threaded flanges, welded flanges, or a flange adapter having a bore which could slide smoothly over the end of the pipe. The adapter was disc-shaped and had a hub which carried radially-extending set screws that pressed down into the pipe to hold the flange in place. Once the flange had been attached to the pipe, the flange was then bolted to the flange of the valve. A flexible seal was inserted between the two flanges and the water-tight connection was complete. It is becoming common practice to use plastic pipe in many hydraulic installations and, in particular, polyvinlychloride (PVC) pipe has become popular. When one attempts to attach such a pipe to a flanged element, using the old flange adapter that has been described, the set screws distort the pipe and even pierce it on occasion. The distortion of the pipe can cause leakage through the space between the flange and the pipe and, under some circumstances the pipe will slide out of the flange because hydraulic pressure. These and other difficulties experienced with the prior art devices have been obviated in a novel manner by the present invention.
It is, therefore, an outstanding object of the present invention to provide a flange for attaching fragile pipe to a flanged element.
Another object of this invention is the provision of an adapter flange for use with pipe which is easily distorted.
A further object of the present invention is the provision of an adapter flange for use in attaching plastic pipe to a fiberglass pipe, or wall steel pipe to a flanged valve or the like.
It is another object of the instant invention to provide an adapter flange for use with soft pipe, which flange is simple in construction, which is inexpensive to manufacture, and which is capable of a long life of useful service with a minimum of maintenance.
With these and other objects in view, as will be apparent to those skilled in the art, the invention resides in the combination of parts set forth in the specification and covered by the claims appended hereto.